4-Bromo-2,3,5-trichloro-6-iodopyridine was studied as a new substrate in chemoselective Sonogashira reactions. This approach provides an efficient access to non-symmetrical mono-, di-, tri- and pentaalkynylated pyridines in good yields. Selected pentaalkynylated pyridines were studied with regard to their UV/Vis- and emission properties showing moderate to high fluorescence quantum yields.

中文翻译：

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化学选择性Sonogashira交叉偶联反应合成非对称炔基吡啶

研究了4-溴-2,3,5-三氯-6-碘吡啶作为化学选择性Sonogashira反应的新底物。该方法以高收率有效地获得非对称的单，二，三和五烷基炔化吡啶。研究了选定的五烷基炔化吡啶的UV / Vis-和发射性能，显示出中等至高的荧光量子产率。